1. Field of the Invention
This invention relates to a feed composition for fowls which improves calcium intake, bone formation and eggshell quality.
2. Description of the Prior Art
Feed compositions for fowls contain a protein source, an energy source, a calcium source, a phosphorus source, vitamins, minerals and the like. The protein is fish meal, soybean cake, rapeseed cake, feather meal, meat bone meal or the like, and as the calcium source, calcium carbonate is blended in a form of shell powder.
Recently, breeding space per one fowl gradually decreased according to the scale expansion and intensiveness in fowl breeding, and as a result, the motion quantity of the fowls gradually decreased. Besides, the fowls were not bred under natural light, and therefore, the breeding circumstances became worse for the bone growth of the fowls. Moreover, in the case of adult chicken for the production of eggs, there is a problem in eggshell quality. In general, eggshell quality of adult chicken for the production of eggs becomes worse after 400 days old. Eggshell also becomes worse in summer season by a high temperature stress. In order to improve the formation of bone and eggshell, commercial feeds usually contain a sufficient amount of the nutrients necessary for forming bone and eggshell such as a calcium source, a phosphorus source, various vitamins and minerals. However, when the blending amounts of these nutrients are increased, there is a limit to the improvement in bone and eggshell formation. Therefore, it is desired to develop another means of increasing calcium intake and improving the formation of bone and eggshell.